The present invention is apparatus for interfacing the actuator arm assembly in a disc drive to control and signal processing circuits mounted external to the disc drive casing. Additionally, the inventive apparatus protects the integrity of the "clean room" environment surrounding selected disc drive components.
In general, a disc drive contains one or more discs capable of magnetically storing information. The discs are rotated by a spindle motor mounted at the center of the disc or discs. The information is read and written to specific locations on the disc or discs using magnetic transducers, commonly known as heads, that "fly" above the disc surface. Head positioning apparatus is provided in the form of an actuator arm assembly.
The actuator arm assembly consists of a substantially triangularly shaped actuator arm. Traditionally the arm is constructed from a low mass material such as cast aluminum. The arm is designed to pivot about a centrally located pivot bore. The bore cooperates with a bearing system surrounding a fixed shaft enabling the arm to pivot smoothly about the shaft.
At one end of the arm is attached a means for moving the arm about the shaft. Typically, the motion is accomplished by a moving coil magnetic motor having the motor coil attached to the arm. Activating the motor coil causes the actuator arm to pivot about the shaft.
Attached at the other end of the arm are transducers for receiving and depositing information to/from the discs. The transducers are commonly known as read/write heads. The electrical signals received by the heads are transmitted via flexible printed circuit cabling (PCC) to a signal processing circuitry located elsewhere in the disc drive. Typically, the signals from the heads are preamplified as near to the heads as physically possible. Thus, preamplification is usually provided prior to sending the signals to other signal processing circuits. To maintain a small disc drive footprint, the control signals carried by the PCC for the voice coil motor and the electrical signals sent to and received by the heads are processed outside of the casing which surrounds the previously discussed disc drive components. The casing maintains a "clean room" environment about the disc drive components.
In previous disc drive designs, the printed circuit cable (PCC) exits the casing through a slot. This design is described in U.S. Pat. No. 4, 933,785. However, a slotted casing design does not protect the integrity of the "clean room" environment surrounding the disc drive components. Even if a rubber gasket or other sealant were placed about the slot, the chances leakage in the future is significant.
An object of the present invention is to provide apparatus for interfacing the printed circuit cable with the externally mounted control and signal processing circuits which protects the integrity of the "clean room" environment.
Another objective is to provide a simplified disc drive construction, wherein the cabling does not protrude from the drive. The inventive apparatus provides a sealed connector interface between the disc drive internal components and the external control and signal processing circuits.